Thread rolling apparatus



Aug. 10, 1954 v, H, FRAY 7 2,685,805

THREAD ROLLING APPARATUS Filed Sept. 2, 1950 3 Sheets-Sheet l IN V EN TOR.

Aug. 10, 1954 v. H. FRAY THREAD ROLLING APPARATUS 3 Sheets-Sheet 2 Filed Sept. 2, 1950 .INVENTOR. 5M,

xiii/ g Filed Sept. -2. 1959 Aug. 10, 1954 Y 2,685,806

THREAD ROLLING APPARATUS 3 Sheets-Sheet 5 Patented Aug. 10, 1954 Application September 2, 1950, Serial No. 182,977

Claims priority, application New Zealan e -0ct0ber 13, 19,49

8 Claims.

i FigureS is an elevation of the thread roller This invention relates to thread rolling apparatus whereby screw threads are formed by a rolling process on blanks of metal thread screws, bolts and the like, the objects of the present invention being thev provision of improved thread rolling apparatus which will very appreciably speed up the forming of the rolled threads on the blanks.

While the known flat plate reciprocally operated type of thread rolling apparatus is that which is in general use,'I am aware that rotary roller type thread rolling apparatus is known, but that it has not come into general use even though devised manyyears ago, because of not being positive and consistent enough in .its action. 1

The present invention has been devised to provide improvements in the rotary roller type of thread rolling apparatus which will enable numhers-of blanks to be progressively roll threaded in the machine at the one time, to enable positive entry of the blanks to the machine at correct intervals to accurately agree with the correct register of the thread startspof the thread roller andthe threaded segment and to give what may be considered as a power feed of the blanks to the machine to-enable same to be disposed horizontally as against the usualinclined positionwhen the blanks are fed to same by gravity feed. 1 V

Broadly the invention comprises improvements in thread rolling apparatus comprising .a thread rolling apparatus havinga threadroller mounted on a spindle. which is rotatably carried by bearings in a head, with the threaded curved face of a stationary segment disposed adjacent to said roller, a gap between said thread roller and the segment, a hopper, for deliveringblanks to a conveyor, feed wheel means forcarrying the blanks from the conveyor directly into the gap between the thread rollerand the segment, guide block means disposed around. portion of the feed wheel to hold theblanks onthe feed wheel while carried thereby, and adrive to-the feed wheel to give it rotation which is. fixed in its relationship to that of the threadroller- In describing the invention, reference will be made to the accompanying drawings in which: Figure 1 shows an elevation of the thread roller and hopper feed apparatus as mounted to a com- 7 mon bedplate.

Figure 2 isa plan view of. Fi g. l, ,but with the bedplate deleted and not showing trays, band guards and such like which areportions of the hopper feed apparatus.

apparatus.

Figure 4 is a side elevation and Figure 5 is a plan view thereof,

Figure 6 is an enlarged plan view of the apparatus in the vicinity of the feed wheel,

Figure 7 is a sectional elevation on line A--B of Fig. 6, a

Figure 8 is a partial sectional plan view taken between the upper and lower portions of the feed wheel,

Figure 9 shows a partial plan view similar to that of Fig. 6 but including an alignment wheel for use when the blanks to be roll threaded have countersunk heads and Figure 10 is an elevation of the alignment wheel as applied to the feed wheel for use on countersunk head blanks.

In the invention, the known thread roller apparatus comprises (see Figs. 3, 4 and 5) a vertical spindle I with a thread roller 2 rigidly secured near the top thereof and mounted in bearings 3 and 4 which extend horizontally from the vertical portionjd of a main frame or head 5 which is rigidly secured to a bedplate or the like 6, provisionbeing made by gearing or the like such asa wormwheel 1 (see Fig. 1) on the bottom of the spindle l engaging a worm 8 on a drive shaft 9 for drive of this spindle I and-the roller 2 thereon, portion of the periphery of the roller 2 being disposed closely adjacent to the curved face Illa (see Fig. 5) of a stationary segment [0 which is adjustably and slightly eccentrically mounted to the vertical portion 5a of the main frame or head 5 so as to leave a gap ll between the roller 2 and the segment ID, the curved face I 0a of the segment Ill being provided with the forming threads which are complementary to the forming threads in the periphery of the thread roller 2, means being provided to enter the blanks to the gap inlet or feed-in end Ila.

Hopper-feed apparatus which is substantially of the type as described in my previous U. S. A.

patent application Serial No. 95,492 of May 26, 1949, now Patent No. 2,639,445 issued May 26, 1953 is also mounted to the bedplate 6 and is used in conjunction with the thread rolling apparatus for feeding the blanks to the latter at the required speed, such hopper-feed apparatus having a rotatable hopper l2, a pair of rollers l3 with a drive spindle M, an endless conveyor belt or band l5 passing over rotatable band wheels l6 and I60, which are disposed at opposite ends of the bedplate B and a rigid bar I! and rubbing strip I8 (see Fig. 6) disposed parallel with the band [5, a vertical gap l9 being presented between the rigid bar I! and the said band 15 down within which the shank portions 20a of the blanks 20 hang, with their heads 2% resting on the top edge of the band l5 and, if desired, on the top edge of the rigid bar 1?.

For the purposes of the present invention, drives to such hopper-feed apparatus are obtained from the drive shaft 9 (see Fig. 2) there being a pulley 21 on the drive shaft 9 connected by belt 22 to a pulley 23 on a countershaft 24, a further pulley 25 on this countershaft" 24 being connected by belt 26 to a pulley 21 on a-pinion shaft 28, the pinion 29 on the latter being in mesh with a gear ring 30 which issecured-to the 1 back of the hopper I2.

The countershaft 24 also transmits a'drive as through skew gearing 3| to the drive spindle 14 of the pair of rollers 13, a further pulley 32 on-the drive shaft 9 being connected by a belt 33 to a --pulley :34 on: a'bevelpinion' shaft? 35, the bevel pinion 36 being in mesh with a bevel wheel' 31 which is secured to the band wheel 16a, the drive shaft 9 itself :being driven asbyan electric motor 38 in a suitable mannersuch as the belts 39' and pulleys 40 and 4 shown' in .the drawings.

The conveyor means as presented by the travelling band l5 and the rigid bar 11, convey the 1 blanks 20 toward 'theth'read rolling apparatus,

special means being provided for removing the blanks from the conveyor means and for eifect- 1 ing entry of same-tothe thread roller apparatus at correct-intervals which will accurately agree withthecorrectregister of a thread start of the thread roller 2 and the third start of the threaded segment l0.

At apoint on such conveyor means where the flexible band 15 passesthe'thread roller apparatusjthe rigid bar 11 ends (see Fig. 6) to permit of "the introduction of a feed wheel 42; such-feed wheel 42' being disposedon a vertical shaft 43 and having ratchet like teeth 42a at the upper and lower portions 42b and- 420 thereon-with a plain reduced diametered portion-42d-between these portions, the teeth- 42a and the recesses or spaces betweensuch-teeth coinciding in the upper and lower portions 42b and 420 of -the-wheel 42, the pitch of the teeth being preferably such as to agree with'the distance between each two starts of the thread rolling portion of apparatus. The periphery "of such feed wheel 42 sweeps across and blocks" the space or gap 19 betweenthe rigid bar l1 and the-travelling band l5,as being just short of in contact with the latter,- and it also sweeps-across'the feed-in -ga Ila between the'thread-roller 2 and the stationary segment it being the-object'of this feed'wheel 42 to pick 'upth'e blanks20' from the conveyor and to divert and carry them into the-said feed-in 'gap -I la of the threadrolling apparatus.

The top level of the'feed wheel 42 coincides with the top level of the conveyor band and similarly coincides withthetop level of the thread roller cut therein to permit of free passage of the' -feed "wheel 42 with justmoderate clearance,t-he-=segment 1 0 presenting tongue like portions I llc'which extend to between the upper and lower portions A 421) and 42c'and also under the lower portion 420.

A rigid guide block 44 has an arcuate face 44a which is disposeda'djac'ent to theside-of the feed i wheel 42; this block extending from-nearl'the band I 5 to near the thread 'roller 2;.therigid sbar;

I! also extending to near the opposite side of the feed wheel 42.

There is a positive drive between the thread roller 2 and the feed wheel 42 so that the slots or spaces between the teeth 42a of the latter will register correctly with preferably every second start Ofi'thQJthIfiQd roller 2,. :the direction of rotation of this feed wheel- 42 being such as to pick up the blanks as travelling to same along the conveyor band l5 and to divert them to the thread roller apparatus which takes them off the feed wheel '42.

v-' I his.-positiyerdrive between the thread roller 2 and the feed wheel 42 comprises (see Figs. 3, 4

-'l5--' and-5)- a gear -whel 45 secured to the top of the threadfirollerj spindle i above the thread roller 2, ,this; gear wheel 45 being in mesh with an intermediate gear wheel 46 which is rotatably mount- -ed-to a bracket 41 which is secured to the head 5, this bracket 4'! carrying a radially moveable arm: 48 ;at:.the' outer end of-c which. a second intermediate gean :49.;-is'= rotatably mounted, the latter 4 being: in mesh withsthe gearv wheel 46. and with the lfeedwheel gea-rtfiflewhich issecured to the feed wheel spindle .43=at.a;level above the feed wheel 42,. thisq-feedx-lwhe'el spindle I435 being rotatably 1 mountedttwithinitheuhearinglhousingportion 5 I a of a bracket 5| which is secured to the head 5.

s lt 'willtvbe;zobviousliithat; otherv positive drives 3Q :could be; applied; between thesthread roller spintile 1. andthefeedwheel 42.

- The apparatus l described is. satisfactory when i -handlingtiblanks which;'have round heads or 'cheesewheads, in'ithatithese:present fiat faces un- 3 derttheir heads-lwhichbear fiat onthe band l5 and the rigid bar H, but the blanks which have countersunknheadsido not travel along the con- -veyor means so uniformly .uprightbecause of. their angular-undersides.

.The result;is 'thatioccasionally ablank 2!] is not trulyupright whendt reaches the-feed wheel 42 and there maybe. a jambing tendencybecause of the shanks-30a not passing fairly to between a the upper and lowenteeth 42a of the-feed wheel upper and lower portions 42band 420.

I To overcomethistdifliculty which applies only in respect of the-countersunk headed blanks, an 2 alignment-iwheel 52 (see-Figs.- 9 and 10) is lo- .cated just above the feedwheel 42 substantially 50 at the position ofentry of the blanks 20 to said -feedxwheel -"42 this alignment wheel 52 having recesses-52a f'ormedi in .its periphery which are such aswill b suited to engage around substani tially hali of a countersunk head.

.55 This 'aligmnent'wheel 52 is freely rotatably disposed on antaxleonthe like 52b-to the top of 2 which a radiala-rm -53 extends horizontally to an integralmr attachedpairof lugs 53a, these lugs 53a being pivotally mounted on a vertical pin 54 which isheld'by aebracket-55 which issecured to J the segment lll onto another suitable rigid part ant -the head 5-, assprings5fi on the pin 54 engaging between"the-bracket 55 andthe lugs 53a to ;tend to force'thealignment. wheel 52towards the band-L15.

In useior-soperation with a supply of.-the blanks i'i20passing.= from the-rotating hopper l 2 along the 1' travelling .conveyoreztheset blanks 22! can travel .only:so;fan as'rthe lfeed=-wheel 42=which blocks the gap :l 9: idowmwithin. which; the shanks :20a of the '75 its teeth 42a to sweep acrossgithis gap la:.of .the

conveyor and as the slots or spaces between the teeth 42a are such as to take only one-blank each, the blanks are caught up by their shanks 20a passing between the teeth 42a and are carcause of the-band l travelling at a greater speed than the blanks travel along the conveyor and because of the opposite sidesof the heads being supported by a rigid non-movable bar I1 and the sharp corner of a tooth 42a of the feed wheel 42 coming to bear hard on a blank 20, the band [5 will bend away from the feed wheel 42 to free the blank so that it correctly enters the feed wheel or drops out of the conveyor.

For this purpose there may beextra clearance between the band l5 and the rubbing strip I 8 in the vicinity of the feed wheel 42, the rubbing strip terminating at the feed wheel 42, if so desired, this however not being essential.

Therotation of the feed wheel 42 is therefore resulting in the blanks 20 being carried 'by same from the conveyor to the feed-in gap l I (from its end Ila) between the thread roller 2 and the threaded segment I0 and at the instant when a start of the thread roller 2 is in correct registry with the thread formation at the leading end of the stationary segment III, the rotation of the feed wheel 42 carrying the blanks in turn into the gap l I at which they become engaged between the roller 2 and the segment I!) to commence their rolling passage through the gap II to thereby have the threads applied thereto, the tongue like portions Illc of the segment IE! guiding the shanks 20a of the blanks 20 into the feed-in end Ha of the gap II from the feed wheel 42.'

The peripheral speed of the feed wheel 42 is such as to be the speed of the travel of the blanks in passingalong the curved path presented by the gap l I, this speed, due to the rolling action of the blanks, being almost exactly half of the peripheral speed of the thread roller 2.

When the blanks 20 to be roll threaded are of countersunk head type as shown in Figs. 9 and 10, the alignment wheel mechanism is applied to the thread roller apparatus and as the spring 56 is yieldingly forcing the alignment Wheel 52 towards the travelling band l5, the blanks 20 encounter this alignment wheel with their heads 20b just as their shanks 20a are approaching the feed wheel 42.

Portions of the heads 20b of the blanks 20 are therefore caused to pass into the recess 52a of thealignment wheel 52, this causing them to assume upright positions if not already upright and thus their shanks 20a. are truly engaged by the feed wheel 42, the rotation of thealignment wheel 52 as caused by the push of the blanks as caused by the travel of the band l5, spacing the blanks apart at the correct intervals for true entry to the feed wheel 42.

I claim:

1. A thread rolling apparatus comprising a frame, a cylindrical roller die having a continuous thread formation about its circumference comprising a plurality of thread starts, means for rotatably supporting said roller die in said frame, a stationary die provided with an arcuate concave face having a thread formation thereon for cooperation with the thread formation of said roller die, means for fixedly connecting said stationary die to said frame with said arcuate face disposed adjacent to said roller die with a gap therebetween through which blanks to be threaded pass, power means for continuously rotating said roller die, a rotatable wheel-like member having a plu- 'rality of axially extending blank-receiving recesses about its periphery, means for rotatably supporting said wheel-like member with its periphery adjacent to the periphery of said roller die near the entry end of said gap between said roller die and said stationary die, means for continuously' rotating said wheel-like member in constant relationship to the rotation of said roller die and at a peripheral speed approximately onehalf of the peripheral speed of said roller die for carrying blanks positioned in said axial recesses directly into said gap between said roller die and said stationary die at an instant when athread start on said roller die is in correct registry with the thread formation at the leading end of said stationary die, means adjacent to the periphery of said wheel-like member at a location spaced circumferentially thereabout from the entrance end of said gap between said roller die and said stationary die for automatically loading headed blanks into said axial recesses in said wheel-like member, and means disposed around portions of said wheel-like member between said last-named means and said roller die for retaining blanks in said IGCGSSGS.

2. A thread rolling apparatus comprising a frame, a cylindrical roller die having a continuous thread formation about its circumference comprising a plurality of thread starts, means for rotatably supporting said roller die in said frame, a stationary die including an arcuate concave face having a thread'formation thereon for cooperation with the thread formation of said roller die, means for fixedly connecting said stationary die to said frame with said arcuate face disposed adjacent, to said roller die with a gap therebetween through which blanks to be threaded pass,

power means for continuously rotating said roller die, a rotatable wheel-dike member having spaced axial recesses about its periphery for receiving blanks the trailing sides of which are evenly spaced circumferentially with respect to each other, means for rotatably supporting said wheellike member with its-periphery adjacent to the periphery of said roller die near the entry end of said gap between said roller die and said stationary die, means for continuously rotating said wheel-like member in constant relationship to the rotation of said roller die and at a peripheral speed approximately one-half of the peripheral speed of said roller die for carrying blanks positioned in said axial recesses directly into said gap between said roller die and said stationary die at an instant when a thread start on said roller die is in correct registry with the thread formation at the leading end of the stationary die, a powerdriven flat band having a portion of one reach thereof adjacent to the periphery of said wheellike member at a location spaced circumferentially thereabout from the entrance end of said gap between said roller die and said stationary die and disposed generally parallel with the axis of rotation of said wheel-like member, a member having a surface substantially parallel with said reach of said band and spaced therefrom a distance greater than the diameter of the shanksof gthe-blanks and less than, the, diameter of the heads, of the blanks and forming withl said reach of said band a groove terminating adjacent to the ;periphery of said wheel-like member, means for 1 moving said band to cause said reach thereof to ,move toward said wheel-like-member, and means disposed around that portion of said wheel-like member between said band and said roller die for retaining blanks in said recesses in said wheel-1 like member.

3. A, thread rolling apparatus comprising. a frame, a cylindrical roller die having a continupus thread formation about its circumference ;,comprising a plurality of thread starts, mean for;

rotatably supporting said roller die in said frame, a stationary die including an arcuate concave face having a thread formation thereon for cooperation with the thread formation of said roller die, means for fixedly connecting said stationary,

1 die to said frame with said arcuate face disposed adjacent to said roller die with a gap'therebetween through which blanks to be threaded pass, 7 power means for continuously rotating said roller die, a rotatable wheel-like member having spaced axial recesses about its periphery for receiving blanks the trailing sides of which are evenly spaced circumferentially with respect to each other, means for rotatably supporting said wheel- T like member with its periphery adjacent to the periphery of said roller die near the entry end of said gap between said roller die and said stationary die, means for continuously rotating said wheel-like member in constant relationship to the rotation of said roller die and at a peripheral speed approximately one-half of the peripheral" speed of said roller die for carrying blanks positioned in said axial recesses directly into said gap between said roller die and said stationary die at an instant when a thread start on said roller die is in correct registry with the thread formationat the leading end of the stationary die, a

power-driven fiat band having a portion of one "reach'thereof adjacent to the periphery of said wheel-like member at a location spaced circum- --ferentially thereabout from the entrance end of said gap between said roller die and said stationary die and disposed generally parallel with --the axis of rotation of said wheel-like member,

'- a member having a-surface substantially parallel with said reach of said band and-spaced therefrom adistance greater than the diameterof the shanks of the blanks and less than the diameter of the heads ofthe blanks and forming with said'reach of-said band a groove terminatingadjacent to the periphery of said wheel'like-rnember,--- means for-moving said band to cause said reach thereof; to move toward said-wheel-like member, guide means disposed around'that portion of said wheel-like member-betweensaid 1 band and said roller die for retaining blanks in said recesses in said wheel-like member, a disk- 1like member disposed just above said wheel-like -member adjacent to the end of said groove, said i. disk-like member having circumferentially spaced axiallyextending slots in its periphery adapted --to receivethe shanks of blanks withtheir heads supported thereby, a spindle or axle for rotatably supportingsaid disklike member, means for supporting said spindleor axle for movement generally perpendicular to the plane of said reach of said band, and means for urging-said disk-like member in a direction to engage the periphery thereof underneath the heads of blanks in said groove.

. 4. A thread rolling apparatus as claimed in 1 claim 1 and comprising means located adjacent to the saidwheel-like member and the entrance end of the said 'gap'for ejecting blanks from said wheel-like member and, causing them toenter the gap betweenthe said roller die, and the said stationary die.

5. A thread rolling apparatus as claimed in claim 1 whereinthesaid wheel-like member comadjacent tothe wheel-like member.

'7. A thread rolling apparatusas claimed in claim 1 wherein the said wheel-likemember-comprises a wheel having upper andlower portions providedwith aligned ratchet-like. teeth in their peripheries and a plane reduced, diameter portion between said pperandlower portion and wherein the said stationary die has slots cut thereinat the v entrance endof the gap between the said thread roller and said stationary die into which slotsthe upper and lower portions of the wheel-like member projects and which slots form a tongue-like portion on said stationary die extending between the upper and lower portions of saidwheel-like member to eject blanks from said wheel-like member and cause them to move into said gap incident to rotation of said wheellike member.

8. A thread rolling apparatus as claimed in claim 3, wherein the said disk-like member disposed above the said wheel-like member has semicircular recesses of countersunk head ,shape formed inits periphery and wherein the said spindle or axle is supported by av radial arm extending from said axle to lugs pivotally mounted on a vertical pin secured in a bracket mounted on the said frame ofthe machine, and

wherein a spring tends to move theradial arm and the wheel at'the end thereof toward the power-driven band.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 295,605 1 Wilson et al Mar. 25, 1884 470,150 Altmeyer Mar. 1, 1892 1,764,607 Cook June 17, 1930 1,844,869 I-Iauger et al. Feb. 9, 1932 

